Posted: Mon Oct 24, 2016 2:16 pm Post subject: What are the way we can improve CPU performance in DB2 qry

Hi All,

i'm doing performance fix for old legacy system code, where one cursor has many sub queries and exists clauses.
i tried to replace that logic using icetool with minimum unload queries in jcls' but it not giving expected savings.

therefore i wanted to know is there anyway below query can be write different way.

If your site is not running a specialty engine, adding one will help CPU performance since some of the DB2 work will be offloaded to the engine. Convincing your management that the savings is worth the $40,000 to $100,000 that the specialty engine costs, however, may be difficult.

Have you talked to your site support group about the query? They may have some suggestions for improvement, and they have more tools to investigate the query than we do.

its based on number of records, basically we are experimenting performance improvement of existing COBOL DB2 module. these are old existing modules which are taking more time day by when more input data has increased. hence we are trying to Save the CPU time by rewriting old big queries and few are putting in jcl's using ICETOOL help.

If your site is not running a specialty engine, adding one will help CPU performance since some of the DB2 work will be offloaded to the engine. Convincing your management that the savings is worth the $40,000 to $100,000 that the specialty engine costs, however, may be difficult.

Have you talked to your site support group about the query? They may have some suggestions for improvement, and they have more tools to investigate the query than we do.

yes, we are planning to work with DB2 team to get more details on this.